Senior police official Col. Mohammad Reza Mehmandar, was quoted as saying that the driver lost control of the bus because of high speed in rainy weather. Mehmandar said 19 others were injured in the accident. They were rushed to hospitals for treatment.

The accident took place on the Izeh-Lordegan road, about 500 kilometers (310 miles) southwest of the capital Tehran.

Iran has one of the world's worst traffic safety records, with more than 400,000 accidents and about 20,000 deaths on its roads every year. The high death tolls are blamed on high speed, unsafe vehicles, widespread disregard of traffic laws and inadequate emergency services.